This invention relates to a transformer comprising:
(a) an outer coil made of an electrically insulating material and having a tubular central part on which is provided an outer winding space that extends between a first and a second outer end portion,
(b) an inner coil former made of an electrically insulating material and having a tubular central part on which is provided an inner winding space that extends between a first and a second inner end portion, which inner coil former has been inserted through an opening provided in the first outer end portion into the interior of the central part of the outer coil former in a manner such that both the two first end portions and the two second end portions engage each other, and
(c) a multi-part ferromagnetic core, having a first core part with a limb inserted through openings in the first end portions into the interior of the central part of the inner coil former.
Such a transformer is known from the Dutch Patent Application No. 7204034 laid open to public inspection. The manner in which the core parts are secured in the inner coil former is not described herein. One usual method by which this can be effected is to glue the two core parts to each other. However, this method is time-consuming and less suitable for a mechanized mounting process.